Malignant neoplasms of the ovary are the cause of more deaths than any other gynecologic cancer. Approximately 26,500 new cases are diagnosed each year in the United States, and about 14,500 deaths occur annually as a result of this disease. Clinicians continue to be frustrated by both the paucity of data concerning the etiologic factors in epithelial ovarian cancer and by the failure to achieve a significant reduction in mortality over the past several decades.